muons Archives

November 16, 2024November 16, 2024 by Alan Boyle

America’s Particle Physics Plan Spans the Globe — and the Cosmos

Illustration showing subatomic particles and galaxies in collision — Particle physics experiments address mysteries at subatomic and astronomical levels. (Illustration by Olena Shmahalo for U.S. Particle Physics)

RALEIGH, N.C. — Particle physicist Hitoshi Murayama admits that he used to worry about being known as the “most hated man” in his field of science. But the good news is that now he can joke about it.

Last year, the Berkeley professor chaired the Particle Physics Project Prioritization Panel, or P5, which drew up a list of multimillion-dollar physics experiments that should move ahead over the next 10 years. The list focused on phenomena ranging from subatomic smash-ups to cosmic inflation. At the same time, the panel also had to decide which projects would have to be left behind for budgetary reasons, which could have turned Murayama into the Dr. No of physics.

Although Murayama has some regrets about the projects that were put off, he’s satisfied with how the process turned out. Now he’s just hoping that the federal government will follow through on the P5’s top priorities.

August 24, 2023August 24, 2023 by Scott Alan Johnston

IceCube-Gen2: 8 Cubic Kilometers of Ice, 5 Times the Sensitivity

The IceCube Neutrino Detector is an observatory unlike any other. Using sensors embedded inside a square kilometer chuck of Antarctic ice, it detects tiny particles called neutrinos, which rarely interact with ordinary matter and are incredibly hard to capture. IceCube has had several major successes in the last few years, including this summer’s announcement of a neutrino map of the Milky Way galaxy. But scientists are pushing up against the limits of IceCube’s capabilities, and plans are in the works for IceCube-Gen2: a detector 5 times as sensitive and 8 times as large, with a radio antenna array across four hundred square kilometers. IceCube Gen2 will increase the number of neutrino detections by an order of magnitude, and will be able to better pinpoint the sources from which the neutrinos are emitted.

August 14, 2023August 14, 2023 by Matt Williams

New Muon g-2 Result Improves the Measurement by a Factor of 2

First results from the Muon g-2 experiment at Fermilab have strengthened evidence of new physics. Credit: Reidar Hahn/Fermilab

At the Fermi National Accelerator Laboratory (aka. Fermilab), an international team of scientists is conducting some of the most sensitive tests of the Standard Model of Particle Physics. The experiment, known as Muon g-2, measures the anomalous magnetic dipole moment of muons, a fundamental particle that is negatively charged (like electrons) but over 200 times as massive. In a recent breakthrough, scientists at Fermilab made the world’s most precise measurement of the muon’s anomalous magnetic moment, improving the precision of their previous measurements by a factor of 2.

May 15, 2022May 15, 2022 by Scott Alan Johnston

Cosmic Rays can Help Keep the World's Clocks in Sync

The world has a robust, accurate timekeeping system that regulates our clocks. Humanity uses it for everything we do, from our financial systems to satellite navigation, computer and phone networks, and GPS. But the current system is not perfect, and has vulnerabilities to cyber-attack and disruption. Given the importance of accurate timekeeping to our society (as a fundamental underpinning of life in the 21st century), experts are always looking for ways to improve the system and add redundancy. Researchers at the University of Tokyo have taken a big step in this direction, developing a new method of time synchronization that takes advantage of cosmic rays to calibrate the world’s clocks.

February 28, 2022February 28, 2022 by Evan Gough

Archeologists are Planning to Scan the Great Pyramid of Giza With Cosmic Rays With Such Detail, They Should see Every Hidden Chamber Inside

The Great Pyramid of Giza (Khufu) in 2005. Image Credit: By Nina - Own work, CC BY 2.5, https://commons.wikimedia.org/w/index.php?curid=282496

The Great Pyramid of Giza might be the most iconic structure humans ever built. Ancient civilizations constructed archaeological icons that are a testament to their greatness and persistence. But in some respects, the Great Pyramid stands alone. Of the Seven Wonders of the Ancient World, only the Great Pyramid stands relatively intact.

A team of scientists will use advances in High Energy Physics (HIP) to scan the Great Pyramid of Khufu at Giza with cosmic-ray muons. They want to see deeper into the Great Pyramid than ever before and map its internal structure. The effort is called the Explore the Great Pyramid (EGP) mission.

April 18, 2021April 18, 2021 by Matt Williams

Fermilab’s Muon g-2 Experiment Finally Gives Particle Physicists a Hint of What Lies Beyond the Standard Model

The Muon g-2 experiment at the Fermi National Accelerator Laboratory (Fermilab). Credit: Reidar Hahn/Fermilab

Since the long-awaited detection of the Higgs Boson in 2012, particle physicists have been probing deeper into the subatomic realm in the hope of investigating beyond the Standard Model of Particle Physics. In so doing, they hope to confirm the existence of previously unknown particles and the existence of exotic physics, as well as learning more about how the Universe began.

At the Fermi National Accelerator Laboratory (aka. Fermilab), researchers have been conducting the Muon g-2 experiment, which recently announced the results of their first run. Thanks to the unprecedented precision of their instruments, the Fermilab team found that muons in their experiment did not behave in a way that is consistent with the Standard Model, resolving a discrepancy that has existed for decades.

December 12, 2018 by Evan Gough

A Supernova 2.6 Million Years Ago Could Have Wiped Out the Ocean’s Large Animals

Artist's impression of a Type II supernova. Credit: ESO

For many years, scientists have been studying how supernovae could affect life on Earth. Supernovae are extremely powerful events, and depending on how close they are to Earth, they could have consequences ranging from the cataclysmic to the inconsequential. But now, the scientists behind a new paper say they have specific evidence linking one or more supernova to an extinction event 2.6 million years ago.

About 2.6 million years ago, one or more supernovae exploded about 50 parsecs, or about 160 light years, away from Earth. At that same time, there was also an extinction event on Earth, called the Pliocene marine megafauna extinction. Up to a third of the large marine species on Earth were wiped out at the time, most of them living in shallow coastal waters.

“This time, it’s different. We have evidence of nearby events at a specific time.” – Dr. Adrian Melott, University of Kansas.

Continue reading “A Supernova 2.6 Million Years Ago Could Have Wiped Out the Ocean’s Large Animals”